DjVu

DjVu ( , like ) is a computer file format designed primarily to store scanned documents, especially those containing a combination of text, line drawings, indexed color images, and photographs. It uses technologies such as image layer separation of text and background/images, progressive loading, arithmetic coding, and lossy compression for bitonal (monochrome) images. This allows for high-quality, readable images to be stored in a minimum of space, so that they can be made available on the web.